Invisible and overlooked, Karaboshi Haruki becomes an adventurer with a single burning goal: to finally stand out. His fate shifts when a dungeon suddenly manifests beneath his Hokkaido home. Through a fortuitous discovery of the «Skill Board,» a rare artifact that converts skill points into accelerated growth, he embarks on an obsessive daily quest into its depths. Can relentless dungeon-diving transform an unremarkable man into someone impossible to ignore?